The Trumps sat on the front pew at Washington National Cathedral alongside Vice President Mike Pence and his wife Karen for the traditional morning service on Saturday after a lengthy day of pomp and protests.

At the second ball of the evening the crowd roared with apparent approval when he asked whether he should "keep the Twitter going".

"It's a way of bypassing dishonest media," he quipped.

As the social media takeover was completed policies from the new administration appeared on the White House website.

Confirming the fears of many environmentalists, Mr Trump underlined his intentions on climate change, saying he is "committed to eliminating harmful and unnecessary policies such as the Climate Action Plan and the Waters of the US rule".

He also said the US would be "committed to a foreign policy focused on American interests and American national security", vowing to pursue "joint and coalition military operations" to defeat ISIS and other radical Islamic terror groups.

Ivanka looked stunning in a burgundy wrap dress with a matching handbag

On the steps of the Capitol Building earlier on Friday the president promised to put "America first" as he set out a nationalist agenda.

The address broke with tradition as he sought to hammer home populist political points against globalisation and the Washington elite.

Promising to "rebuild our country and restore its promise for all of our people", he said: "From this day forward it is going to be only America first, America first."

Around 1.8 million people turned out for President Barack Obama's first inauguration in 2009, but photographs of the National Mall suggest considerably fewer travelled to Washington DC to see his successor sworn in at the Capitol building on Friday.

Meanwhile thousands joined protests in the city, with chaotic scenes outside the Washington Post building where demonstrators torched a limousine.

Elsewhere windows were damaged by people carrying metal poles and hammers, and police had to use hand-held water cannon, smoke grenades and tear gas to disperse the troublemakers, with at least 217 arrested, while six officers suffered minor injuries.

Other protests took place around the world as Mr Trump took the oath of office on the steps of the Capitol building just before noon local time, his family and the outgoing president looking on.

Imploring the US to come together, Mr Trump said that a united America "is totally unstoppable".

All decisions on trade, taxes, immigration and on foreign affairs will be made to "benefit American workers and American families" he pledged.

He added: "America will start winning again, winning like never before."

Prime Minister Theresa May congratulated Mr Trump on taking office, and said that in previous conversations he was committed to strengthening the "special relationship" between Britain and the US.